Burner system, including ignition controlling means



p 1951 F. B. AUBERT 2,569,089

BURNER SYSTEM, INCLUDING IGNITION CONTROLLING MEANS Filed June 19, 1946 9 3/2 40 \OPEN POSITION -425 4|s 420 43a 42a WM 44337 4060. 42l M 436 44 I IN VEN TOR.

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ATTORNEY Patented Sept. 25, 1951 UNITED STATES PATENT OF F I CE BURNER SYSTEM, INCLUDING IGNITION CONTROLLING MEANS This invention relates to new and useful improvements in gaseous fuel burning apparatus and more particularly to means for controllin the operation of a burner igniting means.

An object of the invention is to provide a novel apparatus for controlling the operation of a gaseous fuel burner and its igniting means.

Another object is to provide a safety feature for gaseous fuel burner operation in the event of leakage of gas to the burner or failure of the burner gas supply valve to close.

Another object is to provide means by which the ignition means will be operated for a period followin operation to close the gas supply valve.

The invention consists in "the novel arrangement and cooperative relation of parts in the apparatus, as will be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying drawings, to be taken as a part of this specification, there are fully and clearly shown several preferred embodiments of the invention, in which drawings:

Figure 1 is a diagrammatic view of a gaseous fuel burning apparatus with its control system;

Fig. 2 is a diagrammatic view of a modified burner control system generally similar to that of Fig. 1, and

Fig. 3 is a diagrammatic view of a heating apparatus having another form of controlling system for the ignition means.

Referring to Fig. 1, the gaseous fuel burner 300 is supplied with gaseous fuel through a pipe or conduit 30|, the fiow of fuel being controlled by a manually operable valve 302 having a valve member 303 cooperable with a valve port 333. The valve member 303 is normally urged toward closed position by a helical coil compression spring 303 acting on the valve stem 303. The valve member 303 is movable to open position by a manually operable cam member 301, which may be pivotally secured to the valve stem and have its cam surface bearing on the valve bonnet 301 for example. Secured to the stem 306 and electrically insulated therefrom, there is a switch arm 308 having a flexible resilient portion 303 carrying contacts 3|0, 3H insulated from each other. The contact M is engageable with a fixed contact 3|2 during movement of the valve member 303 to closed position, the valve member 303 being permitted to have continued movement to its seat after engagement of these contacts by reason of the flexible arm portion 303. The contact 3|0 is connected by a lead wire M3 to one terminal of a heater coil 3 which has its other terminal connected by a wire 3H to the main line wire 3l5 leading from a source of current supply. The fixed contact 3|2 is connected by a wire 3|6 to the other main line wire 3H so that when the contacts 3|0 and 3|2 are engaged, then the coil 3 will be energized. The coil 3 is in heat exchange relation and opertill able to heat a thermostatic element 3|8, preferably a bimetal operating arm or blade rigidly secured to a base at one end and at its other end carrying a switch contact 3|9. The blade 3|8, when cold, or when it has cooled following deenergization of coil 3, warps to the right facing Fig. 1' so as to move the contact 3|9 into engagement with a fixed contact 320, thereby closing the circuit of the primary coil 32| of an ignition transformer 322, the circuit bein as follows, from the main line wire 3l5 through a wire '323 to the blade 3? and contact 3|9 and from the contact 320 through a wire 323 to a wire 324% connected to one terminal of the coil 32| and from the other coil terminal via a wire 325 to the main line wire 3|'|. The secondary coil 326 of the ignition transformer is connected by wires 321, 328 to the spark ignition electrodes 329 positioned in cooperative relation with the burner 300 to ignite the gas discharging therefrom when the valve member 303 is opened. The contact 3 is cooperable with a contact 333 and is engageable therewith upon the valve member 303 reaching substantially full open position by operation of the cam member 307. When the contacts 3| I and 330 are engaged with each other, a circuit will be established to the transformer primary coil 32| as follows, from main line wire 3l5 through wire 33H to contact 3H and from contact 330 through wire 332 to the Wire 3323 leading to the coil 32| and thence via wire 325 to the main line wire 3H.

The operation of this apparatus of Fig. 1 is as follows: During the stand-by period when no heat is desired from the burner 300, so that the valve member 303 is closed, the coil 3M will be heated by reason of closure of contacts 3H), 3|2 so that the transformer 322 will be deenergized by reason of the open circuit at the contacts 3l9, 320. When the cam 30'! is manually operated to open the valve 303, the contact 3| i will engage the contact 330, thereby closing the circuit to the transformer 322 as above described, so that ignition sparks at the electrodes 329 will ignite the gas at the burner 300. Opening of the valve member 303 breaks the circuit of heater 3M at contacts 3M, 3|2 so that the bimetal element 3|8 cools and moves to the right thereby closing contacts 3I9, 320. When it is desired to stop further operation of the burner 300, the cam 30'! is moved to the position of Fig. 1 which will break the circuit to the transformer 322 at the contacts 3| l, 330 but the circuit to the transformer primary coil 32f will be maintained through the closed warp switch contacts 3| 9, 320 so that ignition sparks at the electrodes 329 will continue and ignition will be maintained. Therefore, if the closing movement of the valve 303 extinguished the flame at the burner 300, but the valve member 303 failed to close off gas flow through the port 304 to the pipe 30| so that gas flow of ignitable proportions continued to feed to the burner 300, then the continued ignition will ignite the gas leakage to the burner 388. The period of continued ignition is determined and controlled by the time required for heating of the blade 318 by the coil 314, the coil 314 being energized by closure of contacts 318, 312 as the valve member 363 is moved toward closed position. Therefore, a predetermined time after movement of valve member 383 toward closed position and closure of contacts 318, 312, the blade 318 will have been heated sufliciently by the coil 314 to move contact 319 away from contact 328 and thereby break the circuit to the transformer primary coil 321. This predetermined time period for breaking of circuit at contacts 319, 328 is sufficient to assure that ignition will be maintained on long enough to ignite any leakage mixture at the burner 388 following extinguishment of the flame by closing movement of the valve member 383.

In Fig. 2, the burner 358 is supplied with gas from the pipe 351 controlled by the solenoid or electrically operated valve 352 having the operating coil 353. .A circuit having wires 354 and 355 leads to the coil from a switch 356 and main line wire 351. It will be apparent that the switch 356 can be either manually or automatically actuated. The switch 356 is connected by wire 358 to main line wire 359. Leading from the wire 359, there is a wire 368 which is connected to a switch arm 361 which is movable by the stem or armature of the valve 352. Cooperable with a contact on the switch arm, there is a fixed contact 362 from which a wire 363 connects to an electrical resistance heater 364 which is connected in turn to a wire 365 terminating at one terminal of the primary coil 366 of an ignition. transformer 381 from which a wire 318 connects back to the line wire 351. The transformer secondary coil 319 has its terminals connected to spark electrodes 388 which are positioned to ignite the gas mixture discharging from the burner 358; shunting the switch 361, 362, there is a circuit for the primary transformer coil 356. A wire 381 is connected to the wire 368 and to the fixed contact 382 of a thermostatic or heat motor relay switch 383 having a bimetal blade 384 which is connected by a wire 385 to the coil lead wire 365. The wire 381 is shown to include a resistor 381 which represents the inherent internal resistance of the switch and lead wires thereto and therefrom.

The operation of this system of Fig. 2 will in general be clear from that of Fig. 1. The parts are shown in the burner operating position, the main switch 356 having been closed. Upon closure of this switch. the solenoid valve coil 353 is energized to open the valve 352. The opening movement of the valve stem closes the switch 361, 362, thereby energizing the primary coil 366 and the heater coil 364. Sparking at the electrodes 388 ignites the fuel mixture. Shortly after the closure of the switch 361, 362, the thermostatic actuator 384 closes against contact 382 thereby completing the circuit for the primary coil shunting the switch 361, 362. While the closing of the switch contacts 332 and 384 tends to short out the resistor 364 it is merely a matter of proper commercial design to so proportion the size of the resistor 364 relative to the internal resistance 381 of the switch 383 so that sufficient heat will be generated by the resistor 364 to maintain the switch 383 closed even when the shunt circuit is established. Upon opening of the switch 356, the valve 352 will close by gravity or spring force and the downward or valve closing movement of the armature will open the switch 381, 362 to break the circuit to the heater coil 384. Ignition will be maintained, however, until the circuitis broken at contact 382 by cooling of the actuator 384. The time delay before sparking at the electrodes 388 ceases is determined by the regulatable cooling time of the actuator 384 to be of such duration that any leakage of gas through the valve will be ignited before sparking stops. The interval of delay may be of say fifteen seconds duration or such other time as will assure safety in the particular burner.

Referring to Fig. 3, the gaseous fuel burner 488 is fed with fuel from a pipe 481 containing an automatic or electrically operable valve, such as a solenoid valve, 482 having an operating solenoid coil 483 which when energized, opens the valve. The coil is in the secondary circuit of a step-down transformer 484 having its secondary coil 485 connected at one end by a lead wire 486, 486 to one terminal of the solenoid coil 483 which has its other terminal connected by wire 481, 488 to the fixed contact member 489 of an automatic switch 418, such as a room thermostat. From the bimetal blade 411 or thermostatically operated arm and movable contact of the thermostat 418, a wire 412 leads to the other terminal of the secondary coil 485. The transformer primary coil 413 is connected by lead wires 414, 415 to the main line wires 416, 411 respectively of the usual domestic current supply means. Connected between the lead wires 488 and 486,

there is a relay coil 418 of a relay switch 419, a

, break contact when the coil 418 is energized.

The contact 422 is connected by a wire 426 to a wire 426 which is connected to the main wire 416. The fixed contact 424 is connected by wires 421, 428 to one terminal of the primary coil 423 of the ignition transformer 438. From the other terminal of the ignition transformer, wires 431 and 432 connect to the line wire 411. The switch contacts 423, 425 control the circuit of a heater or resistance coil 433 of a thermostatic relay 434 having a bimetal operating blade 435 which is fixed at one end and carries at its other movable end, a contact member 436. A fixed contact member 431 is engageable by the contact member 436 upon cooling of the bimetal blade 435 and is connected by a wire 438 to the junction of the wires 421, 428. The contact member 436 is connected by a wire 439 to the main line wire 416 via the wire 426 so that the relay 434 controls the ignition transformer 438 and is in shunt with the relay contacts 422, 424. The transformer 438 has its secondary coil 44. connected to the spark electrodes 441, positioned to ignite the fuel mixture from the burner 488, by the lead wires 442, 443. The heater coil 433 is connected at one end by wire 444 to the wire 426' from the main line wire 416 and is connected at its other end by wire 445 to the relay contact 425. The movable contact 423 of this relay switch is connected by wire 446 to the wire 432 which leads from the main line wire 411.

The operation of the system of Fig. 3 is as follows: When the room thermostat calls for heat and closes against contact 409, the transformer 404 being energized, parallel circuits will be completed through the relay coil 8 and through the solenoid valve coil 403. These circuits will be as follows: from the transformer secondary coil 405 through wire 2 to and through the closed switch 4" to lead wire 408 and thence branching through wires 4" and 420 respectively to the coils 400 and 4|! from which the wires 406 and 42I respectively connect to the wire 406 which leads back to the transformer coil 405. Energization of solenoid coil 400 will open the valve 402 for gas flow through pipe 4! to the burner 400. The relay coil 4l-0 will close the contacts 422 and 424 and will open the contacts 423, 425 thereby making a circuit through the ignition transformer primary coil 429 and breaking the circuit through the thermostatic relay coil 433. The ignition circuit is as follows: from line wires 4l6, 420 to wire 426, through switch contacts 422, 424 and wires 421, 428 to the coil 429 and thence via wires 434, 432 to the main wire 4H. Energization of transformer 430 will cause a spark discharge across the electrodes 44l which are energized from the transformer secondary coil 440 through the wires. 442 and m and will thus ignite the fuel mixture discharging from the burner 400. The breaking of circuit at contacts 423, 425 will cause the coil 433 and bimetal element 435 to cool and result in making of circuit between contacts 436, 421! which provide an alternate circuit for energizing the ignition transformer, as follows: from line wires 4H5, 426 to the wire 439 and thence through the blade or element 435 and contacts 436, 431 and wire 422 to the wire 424 which is connected to the primary coil 420, the return circuit being from the coil 429 through wires 43H and 432 to the main wire 441. When the room thermostat 4) is satisfied and breaks circuit between blade 4H and contact 409, the solenoid valve coil 403 will be deenergized as will the rela coil M0. Opening of switch contacts 422, 424 will not deenergize the ignition transformer as its circuit is maintained through the contacts 436, 421 as above described. Accordingly, the sparking at the electrodes 44i will continue so that if there is any appreciable leakage at the valve 402, the escaping gas at the burner will be ignited and any explosion hazard will be avoided. The sparking at the electrodes 44! will continue until the heater coil 423 warms the bimetal element 435 sufliciently to move the contact 446 away from the fixed contact 431. The time interval for breaking of contact at 436, 444 as above noted with respect to Fig. 1 may be varied in accordance with the thermostat relay structure and may be of say hall a minute duration.

This application is a continuation in part of my copending application Serial No. 486,829 filed May 13, 1943, for Ignition Controlling Means, now Patent No. 2,406,185 granted August 20, 1946.

Having thus described the invention, what is desired to be secured by Letters Patent of the United States is:

1. A burner safety control apparatus, comprising a burner, a gaseous fuel controlling valve for said burner, electric ignition means for said burner, an electric circuit for said ignition means, a switch in said circuit and open when said valve ing of said valve, a circuit shunting said switch and having a normally open switch therein, thermostatic means controlling the opening and closing of said last-named switch, an electric heater for said thermostatic means, and means operable upon opening of said valve to control the energization of said heater therebyto close said normally open switch, said thermostatic means acting to delay the opening of said normally open switch subsequent to closure of said valve.

2. A burner safety control apparatus comprising a burner, a gaseous fuel controlling valve for said burner, electric ignition means for said burner, an electric circuit for said ignition means, a switch in said circuit and open when said valve is closed, means to close said switch upon opening of said valve, a circuit shunting said switch and having a switch therein, thermostatic means operable when heated to open said last-named switch, an electric heater for said thermostatic means, a circuit including said heater, a switch in said last-named circuit and closed when said valve is closed thereby to energize said heater, and means to open said last-named switch upon opening of said valve so that said thermostatic means will cool and close said shunt circuit switch.

3. A burner safet control apparatus comprising a burner, a gaseous fuel controlling valve for said burner, electric ignition means for said burner, an electric circuit for said ignition means, a switch in said circuit and open when said valve is closed, means to close said switch upon opening of said valve, a circuit shunting said switch and having a switch therein, a bimetal blade cooperable with said last-named switch and ac.ing when heated to open said last-named switch, an electric heater for said blade, a circuit including said heater, a switch in said last-named circuit and closed when said valve is closed thereby to energize said heater, and means to open said lastnamed switch upon opening of said valve so thatsaid thermostatic means will cool and close said shunt circuit switch.

4. A burner safety control apparatus comprising a burner, a gaseous fuel controlling valve for said burner, electric ignition means for said burner, an electric circuit for said ignition means, a switch in said circuit and open when said valve is closed, means to open said valve and to close said switch, a circuit shunting said switch and having a switch therein, thermostatic means operable when heated to open said last-named switch, an electric heater for said thermostatic means, a circuit including said heater, and a switch in said last-named circuit and closed when said valve is closed thereby to energize said heater, said valve opening means acting upon opening of said valve to open said last-named switch so that said thermostatic means will cool and close said shunt circuit switch.

5. A burner safety control apparatus, comprising a burner, a gaseous fuel controlling valve for said burner and having a stem, electric igni.ion means for said burner, an electric circuit for said ignition means, a switch in said circuit and open when said valve is closed, said stem being cooperable with and acting upon said switch to close said switch upon opening movement of said valve, a circuit shunting said switch and having a normally open switch therein, thermostatic means controlling the opening and closing of said lastnamed switch, an electric heater for said thermois closed, means to close said switch upon open- 7 Static means. nd means opera l p n opening of said valve to control the energization of said heater thereby to close said normally open switch, said thermostatic means acting to delay the opening of said normally open switch subsequent to closure of said valve.

6. A burner safety control apparatus, comprising a burner, a gaseous fuel controlling valve for said burner, means for actuating said valve, electric ignition means for said burner, an electric circuit for said ignition means, a switch in said circuit and operable to closed position by said means upon opening of said valve, a circuit shunting said switch and having a normally open switch therein, a second switch operable by said valve operating means and closed when said valve is closed, thermostatic means operable to actuate said normally openswitch, an electric heater for said thermostatic means, and a circuit including said second switch and said heater.

7. A burner safety control apparatus, comprising a burner, a gaseous fuel controlling valve for said burner and having a stem, means operable upon said stem to open and close said valve, electric ignition means for said burner, an electric circuit for said ignition means, a second circuit for said ignition means, a normally open switch in said first-named circuit, a normally open switch in said second circuit and biased toward closed position, a bimetal blade coopervalve, a circuit for said means, a switch in said circuit, electric ignition means for said burner, a circuit for said ignition means, a switch in said last-named circuit and closed by said electrical means upon opening movement of said valve, a circuit shunting said last-named switch and having a normally open switch therein, a bimetal actuator for said last-named switch, and an electric heater in said second-named circuit and operable to heat said actuator to close said shunt circuit switch, said bimetal actuator upon breaking of said heater circuit delaying the opening of said shunt circuit switch upon closing of said valve.

9. A burner safety control apparatus, comprising a burner, a gaseous fuel controlling valve for said burner, electrical operating means for said valve, a circuit for said means, a circuit shunting said operating means, a relay switch having its coil in said shunt circuit, a main switch operable to simultaneously close said circuits, electric ignition means for said burner, a circuit for said ignition means, said relay switch having normally open contacts in said ignition means circuit, a circuit shunting said normally open contacts and having a normally open switch therein, thermostatic means operable when cool to close said last-named switch, an electric heater for said thermostatic means, a circuit for said heater, and normally closed contacts forming part of said relay switch and positioned in said heater circuit.

10. A burner safety control apparatus comprising a burner, a valve for controlling fuel flow to said burner, means controlling movement of said valve toward open position, electric ignition means for said burner, a circuit for said ignition means, an ignition controlling switch in said circuit, thermostatic means operable to actuate said switch, a heating circuit having means for heating said thermostatic means from a cold condition to a heated condition, said thermostatic means in one of said conditions acting to hold said switch closed and being operable to open said switch upon change from said one condition to the other condition, and means operable to control current flow in said heating circuit so as to change said thermostatic means from said one condition to said other condition upon operation of said valve controlling means for valve closing movement, the time interval for change of condition of said thermostatic means delaying the opening of said ignition switch.

11. A burner safety control apparatus comprising a burner, electric ignition means for said burner, a circuit for said ignition means, an ignition controlling switch in said circuit, thermostatic means operable to actuate said switch and having relatively heated and cold. conditions, a circuit having a heater for heating said thermostatic means, a switch in said last-named circuit, a valve for controlling fuel flow to said burner, means operable upon opening operation of said valve to actuate said last-named switch to condition said thermostatic means to move said ignition controlling switch to closed position, said last-named means operable upon closing operation of said valve to actuate said last named switch to condition said thermostatic means to move said ignition controlling switch to open position, the time interval for change of said thermostatic means from said one to said other condition delaying the opening of said ignition switch. 7

12. A burner safety control apparatus comprising a burner, a fuel supply controlling valve for said burner, means controlling opening and closing movement of said valve, electric ignition means for said burner, a circuit for said ignition means, an ignition controlling switch in said circuit, switch actuating means, means interrelating said valve controlling means and said switch actuating means to close said switch upon valve opening movement and to open said switch upon valve closing movement, a circuit shunting said switch, a switch in said shunting circuit, thermostatic means operable on temperature change in one direction to close said last-named switch and on temperature change in the opposite direction to open said last-named switch, means to heat said thermostatic means, and means operable to control said heating means to close said last-named switch on opening movement of said valve and to control said heating means to open said last-named switch on closing movement of said valve, temperature change of said thermostatic means in said opposite direction delaying the opening of said last-named switch.

FRED B. AUBERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,271,822 Zam July 9, 1918 2,221,667 Betz Mar. 12, 1940 

